This invention relates to a novel mold adapted for forming a member from a thermoplastic or thermoset material around a substrate, at some distance from the end of such a substrate. This invention further relates to a novel method for the formation of such a member on a substrate at a distance from the end of said substrate.
The use of molds to form members from thermoset or thermoplastic materials around substrates is well known. One problem in such an operation is the formation of such a member at some distance from the end of the substrate. One particular example is the formation of a flange on the tubesheet of a hollow fiber membrane device. Such membrane devices generally comprise a bundle of hollow fibers wrapped in some fashion about a core, wherein the hollow fibers are held in place by one or more tubesheets. Generally, such bundle of hollow fibers is in the shape of a cylinder. In use, such bundles of hollow fibers or hollow fiber membrane devices are placed inside of a casing. In order to accommodate the placement of the device in a casing, a flange must be placed or formed about the tubesheet of the hollow fiber membrane device. In one method of preparation of the hollow fiber bundle, the hollow fibers are wrapped about the core simultaneously with the formation of the one or more tubesheets. After wrapping the hollow fibers on the core and forming the tubesheet, it is often necessary to form a flange on the tubesheet to enable the placement of the hollow fiber bundle into a casing, along with the accommodation of a seal to seal portions of the hollow fiber device inside the casing from other portions. In many instances, the flange is not formed on the tubesheet or tubesheets at the end of the membrane device and placement of the flange on the tubesheet can become difficult, as the membrane devices are not fabricated to particularly tight tolerances and contain indentations and grooves. Furthermore, it has been in the past required the machining of the ends of the device until you reach the point where you would like the flange to be located. The flange material is then applied and machining is done again to shape the flange to its final dimension. This extra machining is costly and results in extra handling of the hollow fiber device before the casing is placed over the membrane device.
What is needed is process for the formation of a thermoplastic or thermoset member about a substrate at some distance from the end of the substrate wherein the thermoplastic or thermoset material can be kept from leaking onto the extreme end of such substrate. Furthermore, a mold and method which would prevent unnecessary handling or machining of such substrates is highly desirable.